2010 APWA North American Snow Conference 4/20/2010. Jason Bagley Michelle Daum Paul Johnson Mark Devries

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1 Additive Definition Brine Additives Demystified Jason Bagley Michelle Daum Paul Johnson Mark Devries Additive: minor component of a deicing blend used to improve one or more properties Sometimes called agricultural byproducts or organic by-product enhancers/obpe (why?) Not going to discuss MgCl2 and CaCl2 as additives to salt brine. 2 Common Deicing Liquid Uses Pre-wetting salt Direct anti-icing Stockpile treatment, including pre-treated salt Caution: do not pre-treat stockpiles with salt brine Survey Who uses deicing liquids in their program? Who purchases additives? 3 4 Known Additives Corn syrup, corn steeps, and other corn derivatives Beet juice sugared or de-sugared Lignin/lignosulfonate Molasses (usually from sugar cane) Brewers/distillers byproduct/solids Glycerin Before you buy: Define your objectives and resources Temperature/Deicing Performance Corrosion inhibition Residual / stickiness Environmental Cost Storage / Infrastructure Availability Pre-blended with brine Tend to be low-cost products. Why? 5 Match the additive to your objective, not the other way around. 6 1

2 Performance Freeze Point Example Low temperature Freeze point data helpful, but not always indicative of low temperature performance Melting capacity Reflects actual ice melting benefit of additives Why not more data on low temperature melting capacity? ng Point, F Freezin % 70% 80% 90% 100% -5 Salt Brine (100%) Salt Brine 80%, Additive 20% Salt Brine 50%, Additive 50% -10 Dilution Not a beneficial comparison 7 8 Melt Capacity Example Corrosion Inhibition gr Ice Melted per Deicer Liter Ice Melting Capacity, 60 minutes SHRP H Temperature, F Salt Brine 20% Additive Sugar/organic molecules attract oxygen slowing down iron oxidation (rusting) Oxygen scavenging Can be difficult to quantify benefit, but consider: Constituent vehicles Rebar Bridge decks Concrete? Corrosion test on Mild Steel Not a beneficial comparison Don t ignore corrosion from deicing products 9 10 Residual Environmental Can spray roads with more lead time to storm events Keep brine on the road longer, reducing need for reapplication Most (not all) additives improve viscosity Higher viscosity means less runoff and more sticky brine attributes which promotes residual Frictional testing critical State and local specifications PNS (Pacific Northwest Snowfighters) Specify acceptable toxicity levels Corrosion impact must be at least 70% less than salt Don t accept qualifies for PNS list If product not on PNS list, ask for toxicity data Adequate containment Smell

3 Cost Storage/Infrastructure Resources Consider percent needed to achieve your objectives, not just price per gallon $5.00/gal x 3% = $0.15/gal brine $1.50/gal x 20% = $0.30/gal brine Include the cost of application (trucks, overtime, fuel), especially if more product needed to control ice $$$ Tanks versus totes Eutectic temperature of product (indoor or outdoor storage, heated storage) Blending requirements (premixed vs. blend yourself) Mold/spoilage Agitation Salt brine freezes at -6 F Don t miss the mark Vendors Claims versus Reality Additives can help bridge between straight salt brine and high performance brines, such as magnesium chloride or calcium chloride Example: Salt Brine with additive MgCl2 Unit Cost (per gallon) $0.15 $0.80 Additive ($2/gallon x 20%) $0.40 Gallons per lane mile Total miles Cost per storm $8,800 $8,000 Use the right tool for the job 15 Independent testing ask to see verification of claims Does it improve temperature performance of salt brine? Will it freeze up in the tanks outside? How much will it reduce corrosion Why is the product environmentally friendly? Work with reputable companies (including carriers) to avoid frozen syrup or sour milk Hold vendors accountable for performance claims 16 No Magic Bullet Industry Experience Different products with different attributes Establish a test program for your individual conditions Use objective test criteria We just liked it better Everyone else is using it we felt left out Side by side tests Choose the additive that meets your individual needs. Paul Johnson: Wellington County, Ontario Mark DeVries: McHenry County, Illinois

4 TREATED SALT 2002 TREATED SALT Treated salt 2010 Pre wetting and Anti icing icing Units Liquid storage and containment 23 TREATED SALT 24 4

5 Enhanced Brine Manifold Blending Systems Components Salt Brine 85% Organic 10% Calcium Chloride 5% Supermix WE USE ORGANICS AS A PORTION OF OUR MIX COMPONENTS OF THE SYSTEM 120,000 GALLONS OF LIQUID Trial Other Organics

6 Takeaways Define objectives before you buy Independent product analysis Hold vendors accountable for their products Use total cost, not just unit cost Evaluate multiple tools to find the right one for your application Jason Bagley, North American Salt Company (913) ; Michelle Daum, North American Salt Company (913) ; Paul Johnson, Wellington County, Ontario, Canada (519) , Mark Devries, Mc Henry County, Illinois (815) ; 31 6